Effect of iodination site on binding of radiolabeled ligand by insulin antibodies and insulin autoantibodies

Journal Article · Mon Feb 01 04:00:00 EST 1988 · Clin. Chem. (Winston-Salem, N.C.); (United States)

OSTI ID:5243758

Diaz, J L; Wilkin, T J

Four human insulins and four porcine insulins, each monoiodinated to the same specific activity at one of the four tyrosine residues (A14, A19, B16, B26) and purified by reversed-phase liquid chromatography, were tested in a radiobinding assay against a panel of insulin-antibody (IA)-positive sera from 10 insulin-treated diabetics and insulin-autoantibody-positive (IAA) sera from 10 nondiabetics. Of the 10 IAA-positive sera, five were fully cross reactive with both insulin species, and five were specific for human insulin. The rank order of binding of sera with the four ligands from each species was random for IA (mean rank values of 1.9 for A14, 2.0 for A19, 2.5 for B16, and 3.6 for B26 from a possible ranking range of 1 to 4), but more consistent for non-human-insulin-specific IAA (mean rank values 1.3 for A14, 3.8 for A19, 1.7 for B16, and 3.2 for B26 for labeled human insulins; 1.2 for A14, 4.0 for A19, 1.8 for B16, and 3.0 for B26 for labeled porcine insulins). The rank order of binding was virtually uniform for human-insulin-specific IAA (mean values 1.2 for A14, 3.0 for A19, 1.8 for B16, and 4.0 for B26). The influence of iodination site on the binding of labeled insulin appears to be dependent on the proximity of the labeled tyrosine to the antibody binding site and the clonal diversity, or restriction, of insulin-binding antibodies in the test serum. When IA and IAA are measured, the implications of this study regarding the choice of assay ligand may be important.

• Research Organization: General Hospital, Southampton (England)
• OSTI ID: 5243758
• Journal Information: Clin. Chem. (Winston-Salem, N.C.); (United States), Journal Name: Clin. Chem. (Winston-Salem, N.C.); (United States) Vol. 34:2; ISSN CLCHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
ANIMALS
ANTIBODIES
BIOCHEMICAL REACTION KINETICS
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
CHROMATOGRAPHY
DOMESTIC ANIMALS
HALOGENATION
HORMONES
HYDROXY ACIDS
INSULIN
IODINATION
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LIGANDS
LIQUID COLUMN CHROMATOGRAPHY
MAMMALS
MAN
MEMBRANE PROTEINS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PEPTIDE HORMONES
PRIMATES
PROTEINS
RADIOASSAY
REACTION KINETICS
RECEPTORS
SEPARATION PROCESSES
SWINE
TRACER TECHNIQUES
TYROSINE
VERTEBRATES